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Beginners Tutorials

What is a custom block pattern?

A block pattern is a group of blocks, or a block with a predefined content and style.

The purpose of a block pattern is to make it easier and faster to add common design elements and sections to a page or post.

At the time of writing, the block pattern selection is available only when the Gutenberg Plugin is installed and activated.

In the editor toolbar, you will find a new icon which opens a sidebar panel with patterns:

The Block Pattern selection tool is a sidebar in the document settings.

There are four example patterns available by default:

  • Two Columns of Text
  • Two Buttons
  • Cover
  • Two images side by side

How to regsiter a block pattern

To register a block pattern, themes and plugins can use the new PHP function called register_block_pattern.

Note that this function was renamed from register_pattern to register_block_pattern in Gutenberg version 8.1.

You can read the official documentation for the function here:

register_block_pattern accepts a name (prefix), a label, and an array with two parameters: Title and content.

  • Title is the name of the pattern that will be visible in the pattern selection panel.
  • Content is the HTML source code of your block pattern.

Example:

register_block_pattern(
    'theme-prefix/block-pattern-label',
    array(
        'title'   => __( 'Hello Quote', 'textdomain' ),
        'content' => '<!-- wp:quote --><blockquote class="wp-block-quote hello-block"><p>Hello World of Blocks</p><cite>Carolina</cite></blockquote><!-- /wp:quote -->',
    )
);

To get the correct HTML code to use for your pattern, you can do the following:

  • First, create your block pattern in the editor.
  • Then open the editor toolbar, and select Code editor.

Locate your blocks, copy the code, and add it the content parameter.

<!-- wp:quote --><blockquote class="wp-block-quote hello-block"><p>Hello World of Blocks</p><cite>Carolina</cite></blockquote><!-- /wp:quote -->

Since your HTML contains double quotes, “, make sure that the content is wrapped in single quotes, or that you replace the double quotes with \”. Otherwise your code will break.

The preview of the block is created for you automatically.

Custom CSS and identifiers for block patterns

It is worth noting that block patterns have no identifier once they are added to your content.

Even though the patterns have a name and a label, these are not applied to the code.

If you wish to add specific styles, or if you want to be able to identify your block patterns on the front, make sure that you add a custom CSS class while creating the pattern.

Naming block patterns

The name and label of the block pattern must be unique, because otherwise you will overwrite other block patterns.

The title; the visible name of the block pattern, is not unique. So to help identify your patterns, I recommend that you include your brand name, plugin- or theme in the title.

Categories
Beginners Quick guide

Adding custom block styles with PHP

Earlier this year I wrote two articles about how to add custom block styles with JavaScript and CSS files. With the new register_block_style PHP function in WordPress version 5.3, you can achieve the same result by adding custom block styles with PHP, with a lot less code and fever steps.

First, make sure that you have created a child theme. Do not edit the parent theme directly, or you will lose your changes when the theme is updated.

We will be using the same basic gallery block style as in our previous examples.

Open your child themes functions.php file.

To register your block style, copy the following code and add it to the file:

register_block_style(
    'core/gallery',
    array(
        'name'  => 'slug-hide-caption',
        'label' => __( 'Hide caption', 'text-domain' ),
        'inline_style' => '.is-style-slug-hide-caption figcaption { display: none; }',
    )
);

First, we are including the block name: Core/gallery.

Then we are adding three arguments: Name, label, and inline style.

  • Name is the CSS class that will be added to the block to identify it.
  • Label is the name that will be visible in the block’s style selector in the editor.
  • Inline_Style is the CSS code that will be applied to the block.

Remember to change the slug (the prefix), before you save your file.

The style should now be available in the editor:

A gallery block style with hidden captions.

By adding custom block styles with PHP, we can reduce the number of files that we need to include, since register_block_style() already includes the JavaScript and CSS for us.

As the name suggest, the CSS is added inline. Specifically, it is added to the wp-block-library stylesheet.

If you need to dequeue the wp-block-library stylesheet, you need to add the CSS to a different stylesheet that is loaded on the front.


Recommended reading

Categories
Beginners Quick guide

How to add a new default block style

When you add a new block style, you can also make it the default style in the editor.

Revisiting our gallery block where we hid the captions, we only need to add one new line: isDefault: true.

Our example codes would then look like this:

JavaScript:

wp.blocks.registerBlockStyle('core/gallery', {
	name: 'slug-hide-caption',
	label: wp.i18n.__('Hide captions', 'text-domain'),
        isDefault: true
});

Or, if you added the block style with PHP:

register_block_style(
    'core/gallery',
    array(
        'name'  => 'slug-hide-caption',
        'label' => __( 'Hide caption', 'text-domain' ),
        'inline_style' => '.is-style-slug-hide-caption figcaption { display: none; }',
        'isdefault' => true,
    )
);